The effects of successive deposition using continuous heat from a plasma arc on a multi-layer Inconel 718 deposit was investigated using a wire-arc additive manufacturing (WAAM) process with cold metal transfer (CMT). Deposits consisting of 10 layers were manufactured, where interpass time was the only process parameter varied. The shape of the deposits was determined by the interpass time, while microstructural characteristics (growth of dendrite, segregation of chemical component, formation of various phases, etc.) developed due to successive deposition. An aging effect was observed, which caused precipitation of the γ″ and γ′ strengthening phases and the δ phase. The highest hardness value was measured in the middle section of each deposit due to precipitation of the strengthening phases. The cooling rate was calculated using the thermal profile of the deposition process and was found to be slower using the CMT-based WAAM process than that of other additive manufacturing (AM) processes that use laser or electron beams. The results presented here also demonstrated that in-situ heat treatment during deposition is possible using this CMT-based WAAM approach.

使用带有冷金属转移（CMT）的线弧增材制造（WAAM）工艺，研究了使用等离子弧连续加热在多层Inconel 718沉积物上进行连续沉积的影响。制造了由10层组成的沉积物，其中通过时间是唯一变化的工艺参数。沉积物的形状由通过时间决定，而微观结构特征（枝晶的生长，化学成分的偏析，各种相的形成等）由于连续沉积而形成。观察到时效效应，引起γ''和γ'强化相和δ相的析出。由于强化相的析出，在每个沉积物的中部测量到最高硬度值。使用沉积过程的热曲线计算冷却速率，发现使用基于CMT的WAAM过程比使用激光或电子束的其他增材制造（AM）过程要慢。此处提供的结果还表明，使用这种基于CMT的WAAM方法可以在沉积过程中进行原位热处理。